Paul Ryan's addition to the Republican ticket brings a number of advantages, including youth and conservative credentials. One thing he doesn't add is racial diversity. Yesterday, Mitt Romney was campaigning in Florida, a state where more than a third of eligible voters are minorities. NPR's Ari Shapiro offers this look at whether a ticket of two white men is a disadvantage in 2012.

ARI SHAPIRO, BYLINE: Most minority communities in the United States vote solidly Democratic. This is one major exception.

UNIDENTIFIED WOMAN: (Spanish spoken)

SHAPIRO: In the Little Havana neighborhood of Western Miami, El Palacio de los Jugos is an outdoor market and restaurant where local Cuban-Americans do their shopping. Yesterday afternoon, people drank free cups of fresh watermelon, papaya and other tropical fruit juice on ice. They tried to cool themselves with paper fans that said Juntos Con Romney - Together With Romney. When the candidate's bus rolled up, a Cuban-American from the neighborhood took the microphone, someone who also happens to be a Republican senator from Florida.

SENATOR MARCO RUBIO: (Spanish spoken)

SHAPIRO: This is the greatest country in the world, said Marco Rubio.

RUBIO: (Foreign language spoken)

SHAPIRO: There is not another community in this country who understands that better than this community.

Rubio is a local favorite. He was widely considered a frontrunner to be on the ticket until Romney chose Paul Ryan, a Catholic from Wisconsin, instead. To Daniel Nyman, who's originally from Argentina, a candidate's race should make no difference.

DANIEL NYMAN: Personally I don't look at a candidate's face or racial background. I just care what they're going to do for the country and if they have the right idea and the right philosophy.

SHAPIRO: But he also believes that America is not race-blind. He agrees with the widely-held notion that Romney would have a much easier time winning Florida if he had chosen Rubio, because as a Latino, Rubio would bring Latino votes. And Nyman has his own explanation for that phenomenon.

NYMAN: There are people who have no brains and they just vote based on people's racial background.

SHAPIRO: Democrats say they don't get minority votes just by fielding minority candidates. Black people don't vote for President Obama just because he's black, they say. The ideals align. Democrats support immigration reform, affirmative action, poverty programs, as do many minority groups. But running minority candidates on a ticket is also way of saying: I relate to you, you're part of our group. At the Miami rally yesterday, Maria Marvado said her Republican Party didn't do enough of that for a long time.

MARIA MARVADO: They definitely have to be more open to the Latino community. In the past, I think there has been a little bit of separation, but that's not true today.

SHAPIRO: Republicans are working hard to expand their appeal. Several prominent people of color were given prime speaking slots at the party's national convention. But on the campaign trail, the Miami rally was an exception to the norm. At a typical Romney event, the crowd is a sea of white faces, and given the country's demographic trend lines, that could be a problem.

WILLIAM FREY: I think it really is an issue in 2012 as the country is becoming more diverse.

SHAPIRO: William Frey is a demographer at the Brookings Institution. Right now, he says, about 30 percent of American voters are not white. And that number is growing fast, as minorities have more kids at a younger age than whites.

FREY: This may be the last hurrah for older whites in terms of being able to steer the direction of a presidential election. And even then it's sort of iffy, because a lot of the swing states are becoming much more minority. So if those states make a difference, which they probably will, this may not even be the last hurrah for whites. Maybe that last hurrah was elections ago.

SHAPIRO: Mitt Romney disagrees. In a news conference yesterday, he suggested that voters don't care about a candidate's race.

MITT ROMNEY: I think that we recognize people based upon their values and their capacity to get America on track. And I've picked the person who I believe is the right individual to help me if I become president.

SHAPIRO: Today, Romney will campaign in Ohio, where the crowds are likely to look and sound very different from Miami.